The present invention relates generally to compositions and methods for preparing images on substrates having an opaque surface that becomes transparent upon printing. More particularly, the invention relates to utilizing such compositions and methods for the preparation of light-emitting, highly reflective, and/or metallic-looking images on glossy, light emitting, reflective or luminescent substrates. The invention also relates to dry substrates having light-emitting, highly reflective and/or metallic looking images prepared thereon.
Many methods have been used to produce a metallic-looking image on a substrate. For the most part, these methods involve the use of metallic pigments and metal-containing inks. U.S. Pat. Nos. 4,233,195 to Mills, 5,912,283 to Hashizume et al., 5,662,738 to Schmid et al., and 5,766,335 to Bujard et al. describe pigments and ink formulations that incorporate metallic, usually aluminum, particles. While different approaches have been followed to provide enhanced color and pigment variation, the inks and pigments used are typically costly and require complicated and expensive procedures. For example, U.S. Pat. No. 5,370,976 to Williamson et al. describes a metallic color printing process wherein the image is produced using a four-color separation process, involving metallic gold and/or metallic silver separations, and an electronic masking system.
Other processes have been developed for producing a metallic-looking image without the use of metallic pigments. U.S. Pat. No. 5,656,331 to Kline, for example, describes a printed substrate having a metallic finish where the metallic appearance is achieved by applying a first layer having the desired final color pattern, a second layer comprising a moire dispersion pattern and a third coating of water pearl. Complex thermal processing methods have also been used. For example, U.S. Pat. No. 5,564,843 to Kawaguchi describes a method of producing a reflective image by printing the image on the surface of a film using a thermal print head and then affixing the film onto a reflective surface.
Reflective surfaces to form metallic-looking images have also been used, primarily in the marketing and display industries. U.S. Pat. No. 5,106,126 to Longobardi et al. describes a process for reverse printing on a transparent facing material such as a MYLAR(copyright) polyester sheet or a glass sheet. The printing must be done as a mirror image and the printing steps must be performed in an order that is the reverse of the order used in conjunction with conventional printing, making it difficult to use standard printing equipment without substantial modification. Also, this method is quite costly.
A more direct method is provided in U.S. Pat. No. 5,733,634 to Karel wherein a metallic-looking image is generated by first applying a coating of a white pigment to the surface of a reflective substrate, wherein the applied pigment has varying density across the surface, and then applying a coating of a colored pigment, also in varying density across the surface. Those surface areas having a lower density of white and colored pigments have a metallic-looking appearance, as the reflective substrate is visible through the coating layers. This method is effective, it requires a separate screened application of the white dots and is not suitable for use in conventional ink-jet printing or in any other consumer usable image production method.
Accordingly, there is a need in the art for a simple and inexpensive process for the printing of light-emitting, reflective or metallic-looking images.
The present invention features a novel process for producing a light-emitting, glossy, reflective or metallic-looking image utilizing opaque coating compositions on a reflective, glossy, or luminescent substrate wherein the original surface of the substrate is initially masked but, after contact with a recording liquid, becomes transparent, revealing the glossy, reflective or luminescent substrate through the contacted, coated area. The opaque coating compositions are composed of a mixture of a polyacid and a polybase and may be used to treat a substrate either during or after manufacture. Substrates treated with the present opaque coating compositions can be used to yield high quality light-emitting, glossy, reflective, or metallic-looking images.
It is a primary object of the invention to provide a method for producing a light-emitting, glossy, reflective or metallic-looking image comprising the steps of applying an opaque coating composition to the surface of a light emitting, glossy, reflective or luminescent substrate and contacting the coated substrate with a recording liquid, wherein the opaque coating comprises a mixture of a polyacid and a polybase.
Another object of the invention is to provide opaque coatings for the treatment of glossy, reflective or luminescent substrates, which provide a light-emitting, reflective, glossy, or metallic-looking image when contacted with a recording liquid.
A further object of the invention is to provide an opaquely coated reflective or luminescent substrate wherein the opaque coating provides a light-emitting, reflective, glossy, or metallic-looking image when contacted with a recording liquid.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention.
In a first embodiment, then, a process is provided for producing a light-emitting, reflective, glossy, or metallic-looking image comprising the steps of (1) applying an opaque coating composition to the surface of a substrate wherein the surface is selected from the group consisting of glossy surfaces, reflective surfaces and luminescent surfaces and (2) contacting the coated substrate with a recording liquid, wherein the opaque coating composition is such that it becomes transparent upon contact with a recording liquid.
In another embodiment of the invention, a substrate is provided having a surface selected from the group consisting of glossy surfaces, reflective surfaces and luminescent surfaces, coated with an opaque coating composition that becomes transparent upon contact with a recording liquid.
In a further embodiment of the invention, a process is provided for producing a light-emitting, glossy, reflective or metallic-looking image comprising the steps of (1) forming a preselected image or color scheme on top of the surface of a substrate having a surface selected from the group consisting of reflective surfaces and luminescent surfaces, (2) applying an opaque coating composition on top of the preselected image or color scheme, and (3) applying a recording liquid to the coated substrate, wherein the opaque coating composition becomes transparent upon contact.
In a still further embodiment of the invention, a substrate is provided having a surface selected from the group consisting of reflective surfaces, glossy surfaces, and luminescent surfaces, having a preselected image or color scheme on the surface and additionally coated with an opaque coating composition that becomes transparent upon contact with a recording liquid.